tests for vendor from url logic

Signed-off-by: Weston Steimel <weston.steimel@anchore.com>

syft/pkg/cataloger/common/cpe/vendors_from_url_test.go

@@ -0,0 +1,36 @@
+package cpe
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_candidateVendorsFromURL(t *testing.T) {
+	tests := []struct {
+		name     string
+		url      string
+		expected []string
+	}{
+		{
+			name:     "empty",
+			url:      "",
+			expected: []string{},
+		},
+		{
+			name:     "no known vendors",
+			url:      "https://something-unknown.com/126374623876/12345",
+			expected: []string{},
+		},
+		{
+			name:     "gnu vendor from url",
+			url:      "https://www.gnu.org/software/make",
+			expected: []string{"gnu"},
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			assert.ElementsMatch(t, test.expected, candidateVendorsFromURL(test.url).uniqueValues(), "different vendors")
+		})
+	}
+}